The present invention relates to an ink cartridge, and more particularly to an ink cartridge that has specially designed internal air path and ink-refilling hole, enabling the ink cartridge to be more easily produced at reduced bad yield and have extended usable life.
As it is known ink-jet type printers and laser type printers are now two most popular types of printers available in the computer markets. The ink-jet type printers might have an output speed slower than that of the laser type printers, but the former is far less expensive than the latter. As a matter of fact, an ink-jet printer is sufficient to provide very high printing quality for general documents and is much better than the conventional dot-matrix type printers. For these reasons, the ink-jet printers have become widely accepted computer peripheral equipment. With the popularization of ink-jet printers, there is a largely increased consumption of ink cartridges, which form a very important part of the ink-jet printers. Therefore, more and more efforts are made in an attempt to improve the structure and reduce the manufacturing cost of the ink cartridges.
According to an ink cartridge of prior art, the ink cartridge includes a case, a cover, and an ink absorbent made of foamed material. The foamed ink absorbent is disposed in the case that is then closed with the cover and a joint of the case and the cover is sealed. The cover is provided at a bottom surface with a plurality of longitudinal and transverse ribs for pressing against and therefore locating the foamed ink absorbent in the case. A space is left between the bottom surface of the cover and the ink absorbent to prevent a vent hole provided on the cover from being blocked. A blocked vent hole will cause difficulty in good dispensing of ink by the ink cartridge.
The following are some disadvantages of the ink cartridge of the prior art:
1. Both the case and the cover of the ink cartridge are made of a soft resin material. To prevent a finished product of the ink cartridge from deformation, the case is additionally provided with reinforcing ribs along its periphery. Such reinforcing ribs make the mold for forming the ink cartridge more complicate while they are not necessarily effective in solving the problem of a deformed ink cartridge. Such reinforcing ribs also have adverse influence on the appearance of the ink cartridge.
2. Most of the currently available ink cartridges are of disposable type and could not be refilled with ink. That is, once the ink in the case is used up, the whole ink cartridge must be discarded and replaced with a new one. Such disposable ink cartridges are an additional cost to consumers, and form not only an unnecessary waste of reusable resources but also a source of environmental pollution.
3. The cover is provided at its surface with a zigzag venting slot. The zigzag venting slot tends to be clogged by foreign matters during subsequent machining of the ink cartridge. And, since the zigzag venting slot is very narrow, it is easily completely blocked when the cover is still in a molten state.
It is therefore tried by the inventor to develop an improved ink cartridge that can be easily manufactured with reduced bad yield and is environmentally friendly, and therefore eliminates the drawbacks existing in the conventional disposable ink cartridges.
A primary object of the present invention is to provide an ink cartridge having specially designed vent hole and air path that enable easy production of the ink cartridges at reduced bad yield.
Another object of the present invention is to provide an ink cartridge that does not easily deform after being injection molded and is refillable with ink and can therefore have an extended usable life to reduce environmental pollution possible caused by discarded ink cartridges.
To achieve the above and other objects, the ink cartridge according to the present invention mainly includes a cover, a case, and an ink absorbent disposed in the case. The cover is provided with at least an ink-filling hole and a vent hole. No zigzag venting slot is provided on the cover. The vent hole extends downward into the case to form a solid and sealed stub below the cover. A stop disc is put on and around the stub to prevent vaporized ink from entering into and therefore clogging the vent hole. The cover is also provided at a bottom surface with a plurality of spaced transverse compressing ribs which alternately extend from two longer sides of the cover to end at points a distance exceeded a longitudinal centerline of the cover, such that a wound air path is defined below the cover by the staggered compressing ribs. This wound air path below the cover replaces the zigzag venting slot that is otherwise provided on the cover of the conventional ink cartridge, enabling the ink cartridge of the present invention to be more easily produced at reduced bad yield. Air entering into the case via the vent hole can evenly and smoothly flow throughout the case via the wound air path above the ink absorbent to ensure even and smooth supply of ink to an ink-dispensing outlet of the ink cartridge.
For the ink cartridge of the present invention to be structural strong, the case and the cover are integrally made of hard resin material by injection molding and are provided with reinforcing ribs at proper positions.
And, for the ink cartridge of the present invention to have an extended usable life, a capped ink-refilling hole is provided on the cover.